The Samchillian Keyboard...
Okay this is pretty dang cool. From Gizmodo
an experimental musical keyboard by Israeli industrial designer Eitan Shefer, which is a MIDI controller based on relativity. The Samchillian keyboard takes a novel approach to a musical instrument, where you play music not as specific notes but select how they relate to the ones before them. For example, if you're playing a C and then want to play a D, you just push the +1 key. There are two directional keys, 16 keys and eight finger positions, and when you want to bend the pitch or manipulate the filters, you tilt the unit from side-to-side. It's also customizable for large or small hands.